The present study investigates the frequency and intensity of mineral dust emissions over the deserts of eastern Asia from 1996 to 2001. Mineral dust emissions are simulated using a physical dust emission scheme over a region extending from 35.5°N to 47°N and from 73°E to 125°E. The input parameters required by the dust emission model are (1) surface features data including aerodynamic roughnes...

In the atmospheric surface layer, it is widely accepted that ejection and sweep eddy motions, typically associated with coherent structures, are responsible for much of the land-surface evaporation, sensible heat, and momentum fluxes. The present study analyzes the ejection-sweep properties using velocity and scalar fluctuation measurements over tall natural grass and bare soil surfaces. It is ...

Measurements of evaporation were made from July to November 1999 using the eddy correlation method on two wetland types – wet grassland and reedbeds – in south west England. The evaporative water use of a reed bed exceeded that of the grassland wetland by 15% (or 50mm over the 5 months). The evaporation rates at both sites exceed of the Penman Potential Evaporation estimates calculated for this...

A new bulk parameterization of the air–sea momentum flux at high wind speeds is proposed based on coupled wave–wind model simulations for 10 tropical cyclones that occurred in the Atlantic Ocean during 1998–2003. The new parameterization describes how the roughness length increases linearly with wind speed and the neutral drag coefficient tends to level off at high wind speeds. The proposed par...

Surface roughness parameters, such as roughness length and displacement height, impact the estimation of surface moisture, and the frontal areas of buildings and trees are two components that contribute to surface roughness in urban areas. Research on tree frontal area has not been conducted in urban areas before, and we hope to fill that gap in the literature with this study by using Terrestri...

Integrated hydrologic models coupled to land surface models require several input parameters to characterize the land surface and to estimate energy fluxes. Uncertainty of input parameter values is inherent in any model and the sensitivity of output to these uncertain parameters becomes an important consideration. To better understand these connections in the context of hydrologic models, we us...

Surface roughness parameters, namely the roughness length and displacement height, are an integral input used to model surface fluxes. However, most models assume these parameters to be a fixed property of plant functional type and disregard the governing structural heterogeneity and dynamics. In this study, we use large-eddy simulations to explore, in silico, the effects of canopy-structure ch...

We study analytic forms in Fourier space of one-dimensional heightheight correlation functions for self-affine rough surfaces. Comparisons with complex systems suggest three alternative models. However, only the model Cl(k) m (1 + a]#-(r+2H) permits analytic calculation of important surface roughness quantities (i.e. surface width) for roughness exponents in range 0 5 HI 1. Furthermore, the imp...

Wind-tunnel experiments were carried out to better understand boundary layer effects on the flow pattern inside and above a model wind farm under thermally neutral conditions. Cross-wire anemometry was used to characterize the turbulent flow structure at different locations around a 10 by 3 array of model wind turbines aligned with the mean flow and arranged in two different layouts (inter-turb...

Growth of rough polycrystalline silicon films has been achieved on SiO, surfaces over a broad temperature range () 100 “C!) using SiH, chemical vapor deposition at low pressures (mTorr range), with smaller grain structure and roughness length scale achieved at lower temperatures. Rough morphology over a broad temperature range is attributed to the combination of nucleation-controlled initial gr...